How to Master for Streaming

Mastering music has long been the final, necessary step in the production process. While the general goal of mastering hasn’t changed much throughout the years, things like consumer playback systems, formats and artistic desires have. So, what is the best way to master your music for streaming? How do you make your tracks loud? What are LUFS? All these things are important for you to understand when finalizing your tracks for release in today’s most popular audio format: streaming.

While mastering does consist of balancing and controlling a track’s frequencies and dynamics so that it translates across all playback mediums, in modern times, we have the capability to submit different masters for different playback mediums to ensure the best possible listening experience. This means you can upload or submit your mastered audio at different loudness levels so that it better translates to various environments.

While it has been common to submit separate masters for CD and vinyl production for quite some time, the same process is now being applied when uploading music for distribution on popular streaming services like Apple Music, Spotify, TIDAL, YouTube, Amazon Music and more. All these platforms offer guidelines for uploading your finished tracks to ensure optimal playback and fidelity, but they can differ widely in recommended levels, both peak and average.

In the following article, we’re going to break down the best practices for mastering your music for streaming and give you the inside scoop on what you can do to make sure your music sounds the best it can, no matter where it’s being listened to.

Table of Contents

What Are LUFS?
Mixing for Streaming
How to Master Your Audio Tracks for Streaming
   Loudness
   Normalization
   Headroom
Fit Your Format
Why You Should Reference Your Mastered Track
Stream On

What Are LUFS?

Let’s start with defining LUFS, which will be helpful for you to understand as you read further.
LUFS stands for Loudness Units Full Scale. It is a unit of measurement representing the average loudness of a track and is weighted by how humans perceive loudness (Our ears are more sensitive to midrange and high-end frequencies, discerning them to be louder and more powerful than low-end frequencies). Because of this weighting, it differs from typical peak and RMS measurements. Short-term LUFS are measured in three-second increments, while Integrated LUFS measure the entire duration of a track.

Here is a helpful chart for you to reference that provides the recommended LUFS for uploading your tracks to various streaming services. You can find your track’s LUFS by utilizing various plug-ins that provide loudness measurements—typically inserted on your Stereo Bus or master fader.

Streaming Service	Recommended LUFS
Apple Music	Integrated: -16 LUFS Peak: -1dB
Spotify	Integrated: -14 LUFS Peak: -1dB
TIDAL	Integrated: -14 LUFS Peak: N/A
YouTube	Integrated: -13 to -15 LUFS Peak: -1dB
Amazon Music	Integrated: -9 to -13 LUFS Peak: -2dB

Mixing for Streaming

Before we get into mastering for streaming, let’s briefly touch on the importance of a good mix, which sets the stage for successful, effective mastering. While taking things like dynamic range, loudness and clarity into consideration during the mastering phase is important, it’s just as critical to pay attention to these areas throughout the mixing stage as well.

The reason these streaming services want you to submit your songs at certain LUFS is due in part to the applied compression in their normalization processes, which we’ll discuss below. So, an important area of concern (as is typical during the mixing process) is dynamic range.

Pictured: Mixing Console Faders

Overcompressing your tracks can result in a “squashed” or “flat” sound, and this effect can be exacerbated by the added compression of streaming platforms. All of a sudden, the chorus doesn’t “hit” like it used to, and the excitement that was once exemplified in your songs can be lost for good.

This also goes for balance across the frequency spectrum. If your mix is too “boomy” or “muddy,” it can be exacerbated by the loss in quality when your high-resolution files are converted to streaming quality (this also applies to MP3s). When it comes to translation, though, the real magic lies in the mastering stage.

How to Master Your Audio Tracks for Streaming

While you’re forming a sonic vision for how your final mastered track should sound, let’s take a look at some concepts you should be familiar with so that your master successfully translates across a variety of playback systems.

Loudness

Here come the LUFS. One thing fans, artists, producers and engineers generally look for when mastering a project is achieving the desired loudness sought by all parties involved. While certain genres like classical music have a wider dynamic range and may only require minimal (if any) gain to be applied to the final mixes, it’s a common practice in pop, rock, hip-hop and other styles of music to raise the level of the final mix (sometimes, quite significantly) during the mastering process. This can be accomplished by utilizing a single gain stage, or multiple, to raise the level of your track until you achieve your desired LUFS level.

Pictured: Universal Audio Capitol Mastering Compressor Plug-in

Normalization

This process (typically, the default setting) is employed by nearly every streaming service to accomplish one thing—to ensure that different audio tracks play at the same volume level. There are two types of normalization—one called peak normalization, and one called loudness normalization—that adjust the volume based on two different areas of measurement. Peak normalization concerns itself with the highest signals in a track, while loudness normalization adjusts the volume based on perceived loudness.

Normalization is exactly why streaming services have recommended LUFS settings for submitting your tracks. Their algorithm will adjust the volume of your audio to ensure consistent listening volume across their entire platform. This means that if your track’s LUFS reading is above their recommended levels, it will be turned down to match the rest of the listenable material. Conversely, if your track’s LUFS level is below their recommended levels, its volume will be increased to match the other songs available on their platform.

Pictured: iZotope Insight 2 Intelligent Metering Plug-in

Headroom

In addition to LUFS, many streaming services also designate recommended peak levels at which to submit your music. This has to do with headroom. Headroom is the level between your audio’s peak and digital zero. Often referred to as clipping or digital distortion, when your audio “touches” digital zero, audible clipping can occur. So, it’s important to leave space between your track’s peak levels and digital zero. This can also occur when converting audio from digital to analog due to what are called inter-sample peaks. Because digital audio is sampled at specified intervals, but analog audio is continuous, it is possible for your signal’s peak to occur between samples, causing audible distortion. So, leaving extra headroom can ensure the integrity of your audio and keep it clean of cracks and pops.

Pictured: Sonnox Oxford Dynamic EQ Native Plug-in

Fit Your Format

So, you’ve carefully crafted the perfect mix from all your recorded tracks—the band, producer and other creative contributors have all signed off on the project—what comes next? Before you dive headfirst into mastering your track, you should have a clear idea of what formats you’ll be releasing your project in, and the best practices recommended for your tracks to translate seamlessly to each of them.

For a long time, the “loudness wars” drove the volume of music louder and louder with artists chasing hotter mastering levels to stand out among the competition. With CDs, this process was seemingly infinite due to the medium’s large dynamic range. Normalization changed all of that, and now with every major streaming service employing some form of normalization, even the loudest masters are played back at the same volume as the quietest and most dynamic. Unfortunately, these streaming services all use different algorithms to normalize your music, so it’s important to abide by recommended submission guidelines when mastering your tracks for release on each of them. This process can be as simple as adjusting the final gain stage in your mastering chain to achieve the recommended LUFS level, or you can try to further retain the tonality, dynamic range and balance of your tracks by adjusting compression, limiting and gain settings simultaneously to closer match the sound of the other formats you’ll be releasing in.

To elaborate further let’s use an example. If the final gain stage in your mastering chain comes (as is typical) before a limiter, as you turn down the gain to reach your target LUFS reading, the dynamic range—and even tonality—of your track will change. For some genres of music, this extra “breathing room” might be desirable, but for genres like heavy metal, industrial, electronica or hard-hitting rap, this might reduce the punch, crack or impact of the track as a whole—this is most noticeable with transient information like drums. One way to mitigate this effect is to slightly adjust your mastering settings to retain the aforementioned impact, or you can simply turn down the output level of your limiter so that the crest factor of your audio is identical. This involves a detailed set of ears and careful referencing between your masters to ensure they sound as close as possible.

Why You Should Reference Your Mastered Track

Speaking of referencing, this is one of the most important and crucial steps in mastering. Referencing is the act of listening to your track (when checking for tonality, preferably at the same volume) next to other mastered material—this can be accomplished using a simple volume-matching plug-in. This is often done using other songs of the same genre or of a similar composition. Unsure of your track’s low or high end? Listening to your track next to other professionally mastered material can show you how close (or far) you are to “the window.”

Referencing your track can also consist of auditioning it in various playback environments before release so that you can make educated and informed decisions during the mastering process. Do you want to know how your song will sound on earbuds, in the car or on a hi-fi system? Listen to it in these different scenarios so that you can adjust your mastering settings to achieve a balanced and accurate representation of your track across all playback mediums. Things like too much high end can sound harsh on earbuds. Things like too much low end can distort smaller speakers. All of these problems can be carefully mitigated so that your song sounds great everywhere.

Pictured: AKG 240 Studio Headphones and iPhone on Mixing Console

Stream On

People consume music in a plethora of different ways, and it’s not always the easiest task to ensure your song translates artistically in every listening environment. But, equipped with the right knowledge and a little foresight, you can make sure your tracks have the impact and fidelity you want them to, no matter where they’re being listened to.

Because of streaming’s prevalence, it’s essential that you know how to master your music for the most popular streaming services. The way people listen to music will continue to evolve, but with the simple techniques and guidelines described above, you can be confident your songs will sound great on every streaming platform available.